This is where I was at circa 1979...lower powered push/pull amplifiers
with regulated (solid state) power supplies, regulated DC filament supplies,
and gadzooks...running pentodes in triode at 330 Volts Class A. I had
plently of high horsepower pentode amplifiers including some of my own
whoppers...and none of them compared to the quality of these two....the
endless cycle of the auio arts...What is new?.....only our perspective.